Switches are widely used in systems. For example, the Serial Rapid Input Output (sRIO) Gen2 Switch may be used to meet wireless infrastructure customer's requirements for WCDMA/LTE Base Stations.
Quality Of Service (QOS) is an important issue in insuring that data that needs to arrive does so that the transmission does not suffer (e.g. video breaking up, voice dropping out, etc.) Switches are used to handle the data and quality of service is important across switch fabric. Certain traffic type may require reliable transfer without any packet loss through packet retransmission with low latency. Other traffic types can afford to be lossy but require maximum throughput and minimum latency. Under multiple Virtual Channels (VCs) with mixed Reliable Transfer/Continuous Transfer (RT/CT) modes, it may be difficult to handle packet retransmission for a VC in RT mode and silently discard the packets for a VC in CT mode. As a result, network traffic cannot be optimized especially when many packets are outstanding with large packet sizes. This presents a problem.